Piston ring



PISTON RING Filed Sept. 4, 1928 mm T' l :Chutlcs fl iglmson E g %WW:F,V

Stem-Regs;

UNITED STATES PATENT OFFICE CHARLES E. JOHNSON, F MUSKEGON, MICHIGANPISTON RING Application filed September 4, 1928.

This invention relates to piston rings and is concerned with a novelconstruction of oil collecting and draining piston ring which is simplyand easily manufactured and is particularly effective to scrape andcollect any excess oil which may adhere to the walls of a cylinder anddrain the same through the ring to the ring grooves in which the ringsare seated, it being common practice to provide the ring grooves withpassages to carry the oil therefrom to the interior of the piston andthus return it to the crank case.

The present invention is concerned with cutting slots from the outercurved to the inner curved sides of a piston ring and loeating the slotsin two different planes one above the other but having the ends of theslots overlap with the ends of the slots in one plane communicating withthe ends of the slots in the other plane.

An understanding of the invention and the construction embodying thesame may be had from the following description taken in connection withthe accompanying drawing, in which,

Fig. 1 is a plan view of a piston ring constructed in accordance withmyinvention. Fig. 2 is an edge view thereof.

Fig. 3 is a fragmentary enlarged horizontal section through the ring,the plane of the section being taken lengthwise of the upper series ofthe slots in the ring.

Fig. 4 is a front elevation of the construction shown in Fig. 3.

Figs. 5 and 6 are views similar to Figs. 3 and 4, respectively, of aslightly difierent form of construction of the invention, and

Fig. 7 is a vertical transverse section through the ring on the plane ofline 77 of Fig. 3 looking in the direction of the arrow.

Like reference characters refer to like parts in the different figuresof the drawing.

The piston ring 1, in the beginning, is of the ordinary snap ring typeof'construction of uniform cross section throughout its entire lengthand having a parting, indicated at 2 at one side, it being understoodthat the ring normally springs apart, when free to do so at said partingbut when it is closed, as it is Serial N0. 303,796.

in use around a piston and in a cylinder, it is of circular form.

' The ring as thus constructed is provided with two series of slots 3and 4 cut through the ring between its upper and lower flat sides fromits outer curved to its inner curved sides. The upper series of slots 3are spaced apart around the ring and are preferably cut with a circularsaw so that the slots are longer at the outer curved side of the ringthan they are at the inner curved side thereof.

Similarly the lower series of slots 4 are cut with a circular sawthrough the ring and are longer at the outer curved side of the ringthan at its inner curved side.

The horizontal plane of the lower sides of the slots 3 is substantiallycoincident with the horizontal plane of the upper sides of the lowerslots 4. This makes a direct communication between the ends of theadjacent slots 3 and 4 as fully shown in Figs. 2,3 and 4.

It is of course evident that the slots 3 and 4 may be cut with saws ofdifferent diameters so as to vary the shapes of the slots. In Figs. 5and 6-the slots 3 and 4 are cut with saws of greater diameter than thoseused in the construction illustrated in Figs. 3 and 4. This causes theends of the slots to overlap to a greater extent; and the desired extentof overlap may be governed by the selectionof the saws used to cut theslots through the rm O ne of the outstanding advantages of this ring atits uniform strength and resiliency at every point. Where r ngs of thischaracter have heretofore been made with a plurality of spaced apartslots the ring would be comparatively stifi and unyielding at the spacesbetween the slots and relatively resilient where the metal was cut awayto form the slots. By providing two series of slots in different planesand overlapping the ends of the slots as provided by this invention thering has a substantially equal amount of metal in its cross section atall points and therefore its strength and resiliency is substantiallyuniform at all points.

Another desirable feature of the ring is the widened space on the outerperi hery where the ends of the slots overlap. T is provides in thefirst place an added amount of open space on the periphery to pick upand accumulate oil and in the second place it has a tendency to preventthe collecting of carbon in the slots. Where individual slots have beenused it has been found that the carbon deposit in the slots would firstaccumulate at the ends thereof and then build up toward the center untilthe slots were completely filled. With the ends of the slots overlappingand joining each other as in this invention the pocket to convenientlyreceive the oil gives greater force to the oil at this point and flushesthe ends of the slots more freely with oil which reduces carbon depositat this point and the tendency for the collection of carbon in the slotsis greatly reduced. Because of the possibility of varying th length ofthe overlapping of the slots by changing the cutter with which the slotsare formed as heretofore described, it is easily possible to manufacturethis ring to accommodate different engine conditions. If it is notdesired to have an exceedingly overlarge oil collecting opening in theperiphery of the ring the slots are only slightly overlapped but if alarger opening is desired the slots are cut to overlap each otherfarther to the extent necessary to provide suflicient opening on theperiphery to properly collect the oil under the conditions where thering is to be used.

The invention is defined in'the appended claims and is to be consideredcomprehensive of all forms of structure coming within theirscope.

I claim:

1. A piston ring having a series of spaced apart horizontal slots cuttherethrough from its outer curved to its inner curved sides, all of theslots of said series lying in the same horizontal plane, a second seriesof horizontal slots similarly cut through said ring and lying below thefirst series, the slots of the second series being in staggered relationto those of the first series and having their ends overlapping the endsof the adjacent slots of i said first series, the plane of the upperside of the slots of said second series being substantially coincidentwith the plane of the lower side of the slots of the first series.

2. A piston ring having two series of arcshaped slots therethrough fromits outer curved to its inner curved sides, said slots of each of saidseries being spaced apart around the ring and the slots of one seriesbeing in staggered relation with those of the other, said slots beinglonger atthe outer curved side of the ring than at the inner curved sidethereof, with the plane of the upper side of the lower series of slotssubstantially coincident with the plane of the lower side of the upperseries of slots, whereby, the slots overlap each other at their ends andare in communication with each other.

3. A piston ring having a number of arc-

